Don't think FR have won the market but as EI have a 1 million seat sale on that would be the main reason for reduced prices.
EI have more flights between LGW - DUB than FR and they adding more for the winter.
The price bmi are charging is way to high and if it doesn't come down then the early morning flight will be gone.
Its only a trail for the winter as at the monument LH are returning to the normal FRA departure time from end of March and if they do continue next summer I don't think both will get slots at that time of the morning.